Battery plate coating apparatus

ABSTRACT

In the manufacture of battery plates, particularly battery plates for lead-acid batteries, paste is placed on a grid in the usual way, but instead of being forced through the grid by a pasting machine as is conventional, the pasted grid is caused to pass through a gap between a probe and a support. The probe dips into the paste and is vibrated at a frequency to cause the paste to flow into the grid.

D United States Patent 11 1 1111 3,747,560 Roberts et al. July 24, 1973BATTERY PLATE COATING APPARATUS [51] Int. Cl. B05c 7/00, B05c 11/02 75Inventors: Maurice Roberts [58] Field of Search 118/57, 324, 100, 1HamptomimArdgn; John Derek 118/120, 230, 223; 134/1; 259/DIG. 43

Harris, Solihull; Roy William Humpage, Solihull; Geoffrey GeorgeReferences C ted Crow, Solihull, all of England UNITED STATES PATENTS[73] Assignee: Joseph Lucas (Industries) Limited, 2,784,119 3/1957McCown et al. 134/1 Birmingham England Watson X 2,981,268 4/1961 McAuleyet al.. 134/1 X [22] Fllfidi Dec. 18, 1969 3,012,901 12 1961 Reese 112157 ux pp NO 886 270 3,467,063 9/1969 Brinkley et al. 118/324 X RelatedUS. Application Da Primary Examiner-John P. McIntosh [60] Division ofSer. N0. 814,563, April 9, 1969, Att rney-Holman & Stern abandoned,which is a continuation-in-part of Ser. No.

[30] Foreign Application Priority Data In the manufacture of batteryplates, particularly bat- F b 17 1967 G t B .tain 7 698/67 tery platesfor lead-acid batteries, paste is placed on a i "32996/67 grid in theusual way, but instead of being forced u y ma through the rid b a astinmachine as is conven- Se 1 5 1967 Great Britain 40 536/67 g y p g ptional, the pasted grid is caused to pass throu h a gap Nov 27 1967Great Britaln 53 780/67 g A 1968 G t B l9591/68 between a probe and asupport. The probe dips into the Tea n m paste and is vibrated at afrequency to cause the paste 52 US. Cl 118/57, 118/120, 118/223, the

118/230 10 Claims, 7 Drawing Figures PATENIEBJULZMQH SHEET 2 BF 3 MW E wa AT ENEYS PATENmJuLwm 3 747. 56 O INVENTOES ,4 M M Wm, 4 MM WENEYSBATTERY PLATE COATING APPARATUS This application is a divisionalapplication of parent application Ser. No. 814,563 filed Apr. 9, 1969,now abandoned which application Ser. No. 814,563 was acontinuation-in-part of our application Ser. No. 704,011 filed Feb. 8,1968, now abandoned.

This invention relates to apparatus for the manufacture of batteryplates, particularly plates for use in leadacid batteries.

In manufacturing a battery plate it is necessary to apply a paste ofmaterial to an electrically conductive grid and then to ensure that theinterstices of the grid are filled with the paste. Depending on thebattery being manufactured, the grid may be over-pasted (i.e. the pastestands proud of the grid) on one or both faces of the grid.

Conventional techniques employ some form of mechanical device to forcethe paste into the interstices of the grid, and the forces involvedimpose some limitations on the thickness of the grids used, because ifthe grid is too thin it will buckle under the applied force. The actualthickness limitations of course depends on the material from which thegrid is made. The present invention constitutes apparatus for use in acompletely new approach to the problem of pasting a grid, and, for agiven grid material, permits thinner grids to be used than inconventional processes, with consequential reduction in the overallweight of the resultant battery.

The apparatus is used to perform a method which is characterizedessentially in that paste is placed on one face of a grid and caused toflow into the interstices of the grid by vibrational energy, preferablyultrasonic vibrations. Audible vibrational energy is not preferredbecause steps must be taken to protect personnel. Using the preferredapparatus; grids have successfully been pasted by supplying paste to oneface and causing it to flow into the interstices of the grid usingultrasonic vibrations. Enough paste can be caused to flow into theinterstices to ensure that, for some purposes, a plate formed in thisway is satisfactory. However, it is preferred to cause the paste to flowinto and through, and then to invert the grid after the paste flowsthrough, and subject said opposite face to further ultrasonicvibrations, with or without the addition of more paste.

An example of the invention is illustrated in the accompanying drawingsin which:

FIG. 1 is a schematic flow sheet,

FIG. 2 is a fragmentary plan view of part of a conveyor shown in FIG. 1,7

FIG. 3 is a part-sectional view through the conveyor and sonotrode,

FIG. 4 is a sectional view of an ultrasonic tool of which the sonotrodeforms part,

FIG. 5 is a perspective view of the sonotrode FIG. 6 is a perspectiveview of another form of sonotrode, and

FIG. 7 is an end view of the sonotrode shown in FIG. 6.

METHOD The preferred method is best explained with reference to FIG. 1.Grids 21 are fed by any convenient known means to a conveyor 22. Abovethe conveyor 22 is a device 23 for supplying a paste of active materialto the grids 21. The grids with the paste on their upper face are thenfed onto a support 24 located beneath a sonotrode 25, the ultrasonicenergy from which causes the paste on each grid 21 to flow into theinterstices of the grid. In the example shown, it is desired tooverpaste both sides of the grid, and so the support 24 is in the formof a bar with channels extending around the upper part of itscircumference, the arrangement being such that the paste flows into andthrough the grid and so into the channels, but leaves the channels asthe grid leaves the support 24, so that there will be ribs of pasteextending longitudinally on the lower face of each grid 21. The gridsare inverted and fed to a further conveyor 26 which feeds the grids to afurther support 27 in the form of a plain roll, the support 27 beingpositioned below a second sonotrode 28 which smooths the ribs so thatboth faces of the grid are overpasted. Finally, the grids are fed to anoven 29 and dried in conventional manner.

Although the invention is applicable to other plates, the preferredexample is used to manufacture plates of lead-acid batteries. The pasteused is a conventional paste, the constituents of which depend onwhether a positive or a negative plate is being made. The consistency ofthe paste is not critical, but a figure of about 24 units on the Globepenetration scale is preferred. Approximately 100 grams of paste wassupplied to each grid, the grid dimensions being 4.875 inches by 4.5inches, and the grid thickness being 0.065 inches. The frequency of thesonotrode 25 is not critical, and frequencies of up to 24 KC/S have beenused, this upper figure being dictated solely by the frequenciesavailable from commercially produced ultrasonic tools. The amplitude ofvibration of the sonotrode can vary the nature of a finished productslightly and it can be anywhere in the range of 0.0001 to 0.01 inches, atypical preferred figure being 0.002 inches when manufacturing leadplates for use in a battery for a road vehicle. The power available forthe sonotrode is also noncritical provided that sufficient power isavailable to prevent the sonotrode, which clips: the paste, frombecoming substantially damped by the paste. A 600 watt sonotrode hasgiven satisfactory results. Using the preferred figures quoted, it hasbeen found possible to paste grids satisfactorily with the conveyor 22travelling at feet per minute, which compares very favor ably withconventional pasting machines. i

The preferred method disclosed is, of course, capable of considerablevariation. By wayof example only, further paste can be added to eachgrid 21 if required as by means .just before the grid reaches thesonotrode 28. If it is not required to overpaste on both sides of thegrid, or if it is required to paste on one side only, then the ribbedroll 24 can be replaced by a plain roll, and satisfactory results can beachieved without the inversion and further operation by the sonotrode28. The paste could also be placed on the grids by hand. It should alsobe noted that the ribs of the roll 24 are merely to provide support forthe grids, and if the grids are self-supporting the ribs are notrequired. In this case overpasting of both sides of the grid could beachieved in a single vibration by having the grids spaced from a plainroll 24.

Successful results have been achieved with a wide variety of grids. Forexample, dispersionstrengthened lead grids can be used, whether suchgrids are formed by rolling, stamping or any other technique, andwhether the ribs of the grid are at right-angles or extend diagonallywith respect to the frame of the grid. Successful results have also beenachieved with synthetic resin grids coated with conductive material. Ithas been found possible to paste grids up to 0.25 inches in thicknessusing a single sonotrode, or up to 0.5 inches in thickness using thedouble sonotrode arrangement shown in FIG. 1 with paste being addedbefore operation by the second sonotrode.

APPARATUS Parts of the apparatus have already been mentioned briefly inthe description of the method, but the preferred apparatus forperforming the preferred method will now be described in detail. Theapparatus disclosed is actually intended for pasting lead grids whichare cast in conventional manner in the form of a pair of grids joined attheir bases, the lugs extending from the sides of the grids opposite thebases. Such a pair of grids is shown at 31 and 32 in FIG. 2, with theirlugs at 31a and 32a respectively. The lugs 31a, 32a, rest on a pair ofroller chains 33, 34 the rollers of the chains running on supports 35,36 forming part of the frame of the machine. The bases of the grids 31,32 rest on a rail 37 which also forms part of the frame of the machine,and the grids are driven by fingers 33a, 34a upstanding from the chainsrespectively and engaging the lugs. The spacing between adjacent saidfingers is slightly greater than the width of a grid. It will beappreciated that the chains 33, 34 can be driven in any convenientmanner, and with their associated supports constitute the conveyor 22shown in FIG. 1.

Reverting to FIG. 1, the device 23 is in effect a combined paste mixingand feeding station. The constituents of the paste are inserted into ahopper 38 containing any convenient form of mixer (not shown), and thepaste is extruded from the hopper 38 through a nozzle 39 in the form ofa strip of paste, conveniently of rectangular or elliptical crosssection. Mounted forwardly of the nozzle 39 is a rotary cutter 41 whichconsists of a central shaft 42 extending between end plates which carrya pair of wires 43 extending parallel to the shaft 42. The arrangementis such that as the shaft 42 rotates, each wire 43 in turn cuts into theextruded paste, the effect being that each grid in turn is coated withflakes of paste over its upper face. The relative speeds of the variouscomponents can be adjusted to give the required amount of paste on eachgrid, but if for any reason extreme accuracy is required, some form ofsensing device can be incorporated to determine the amount of paste oneach grid and adjust the relative speeds of the various components togive the exact amount required. I

Referring now to FIGS. 2 and 3, the bar 24 is formed from steel, and iscarried by a mounting block 44. Super heated steam is fed by way of apipe 45 through the mounting block 44 to the interior of the bar 24 tobe heated to a temperature in the range 120C. to 200C., the purpose ofheating the bar 24 being to facilitate removal of the grid from the bar.If necessary, a jet of air could also be used to facilitate removal. Theupper half of the bar 24 is formed throughout its length withcircumferentially extending semi-circular channels 46 having a maximumdepth at the uppermost part of the bar.

The sonotrode 25 mounted above the bar 24 is shown in perspective inFIG. 5. It will be noted that in the preferred form the sonotrode has aninclined face 51 which is presented to the grids as they are traversedpassed the sonotrode the purpose of the face 51 being to guide the pastebeneath the sonotrode. It is found preferable for the face 51 to presentan angle of between 30 and 45 to the horizontal. It may be desirable tohave the axis of the sonotrode at an angle other than 90 to thedirection of movement of the grid, but the angle of 30 to 45 would stillpreferably be returned. The sonotrode 25, as shown in FIG. 4, forms partof an ultrasonic tool including in addition to the sonotrode 25 avelocity transformer 52 and a transducer 53 including an energizingwinding 54. The tool is mounted in a container 55 with the upper surfaceof the transducer 53 bearing against a rubber block 56 at the top of thecontainer, the lower part of the container being closed by a mountingblock 57. Between the mounting block 57 and the velocity transformer 52is a further rubber pad 58, whilst acting between the block 57 and afurther part of the velocity transformer of reduced section is amounting bush 59 the purpose of which is to mount the velocitytransformer. The bush 59 is formed from low energy absorbing material,for example p.t.f.e., and its purpose is to mount the lower end of thetool whilst permitting the tool to be adjusted axially, without thenecessity of having a rigid mounting sited at a nodal point. In order toprovide for fine adjustment of the sonotrode 25 with respect of the bar24, bolts 61 are provided with a sliding fit in the block 57 and extendthrough holes in the annular block 58 into screw fitted engagement withthe velocity transformer 52, so that by adjusting the bolt 61 theposition of the sonotrode 25 with respect to the block 57 can beaccurately determined. The tool is water cooled, and for this purposethere is provided a water inlet 62 from which water is fed through atube 63 extending to the lower part of the casing 55, the water leavingthe casing by way of an outlet 64 at the upper end of the casing.

The casing 55 is mounted for movement in a vertical plane to give coarseadjustment of the position of the sonotrode 25, and is also mounted formovement in a lateral direction to paste the double grid referred topreviously, four ultrasonic tools are used. The pairs of ultrasonictools are similar, and so only one pair will be described. The reasonfor using a pair of sonotrodes side by side for a grid is thatcommercially available sonotrodes are not sufficiently wide to cope withgrids of the dimensions previously indicated. The sonotrodes form partof separate tools, and it is for this reason that the sonotrodes 25 mustbe accurately positioned so that the grid when pasted, will have thesame level of paste on the two halves corresponding to the twosonotrodes respectively. A p.t.f.e. shim can be provided betweenadjacent surfaces of the sonotrode in a pair if necessary.

In order to mount the casing 55, there is provided a pair of pillars onwhich is mounted a vertically movable slide 66. The slide 66 has at itsforward end a pair of flanges 67 which are trapped between the casingand mounting plates 69 which are secured to the flanges 68 on the casingby bolts 71. The casing 55 can be moved vertically on the pillars 70,and by releasing the bolts 71 lateral movement of the casing can beobtained.

Reverting now to FIG 1, the grids leave the sonotrode 25 still on theconveyor 22, and pass beneath a heated doctor blade 72. The purpose ofthe blade 72 is to smooth the small ridge of paste resulting from theinevitable small spacing between the pair of sonotrodes 25 acting on agrid. After passing the blade 72, the grids are fed past a sensing head73 to a rotary device 74 which inverts the grids and feeds them to theconveyor 26. Movement of the device 74 is controlled by the sensing head73. The conveyor 26 feeds the grids onto the bar 27, which has nochannels, and whilst on the bar 27 the sonotrode 28, which convenientlyforms part of an ultrasonic tool of the same form as the tool includingthe sonotrode 25, smooths the ribs of paste which were formed as aresult of the channels in the bar 24. There will, of course, be a pairof sonotrodes 28, and after leaving the bar 27 the conveyor 26 feeds thegrids past a further doctor blade 75 to an oven 29 for drying the paste.When the grids leave the oven 29 they pass a further sensing head 74 andthen are fed to a further rotary device 76 having combined therewith aninternal rotating brush 77 and an external rotating brush 78. The designof the device 76 is such that the sides of the grid are exposed, and areacted upon by the brushes to remove any excess material from the sidesof the grid. There is no need to brush the sides of the grids whichincorporate the lugs, because the edges of the sonotrodes above theresides are protected from paste spreading beyond the edges 31b, 32b shownin FIG. 2 by plates 82 (FIG. 2) fixed in a vertical plane relative tothe machine, but spring loaded into engagement with the sonotrode in anyconvenient manner. The vertical position of each plate 82 is such thatit is as close to the top of the grid as practicable. Each of theoutermost pair of sonotrodes also has associated therewith a plate 81which is co-planar with the sloping face of the sonotrode and fixedrelative to the frame of the machine, the plates 81 preventing pasteflow up to the sonotrode.

Turning once again to FIG. 1, any convenient means indicated at 85 isused to separate the pairs of grids when they leave the device 76.

It will, of course, be appreciated, that the apparatus can be modifiedin a variety of ways. One particular important modification is thereplacement of the conveyor 22 by a sprocket-type drive, the sprocketsengaging holes formed along the edges of the grids. This arrangementcannot be employed with the particular form of grids shown, but thegrids can readily be moditied so that their lugs point inwardly. Thistechnique is particularly suitable for use with synthetic resin grids,and has the additional advantage that the conveyor 22 can be formed intwo parts on opposite sides respectively of the sonotrode 25. The partof the conveyor on the left hand side of the sonotrode 25 can then bedriven faster than the other part of the conveyor, so that there is alarger spacing between the grids as they are presented to the device 74.

In certain circumstances, a pair of sonotrodes which are acting on asingle grid can each be inclined to the horizontal with their adjacentedges uppermost. This arrangement produces a grid in which the paste isthicker at the middle of the grid than at the edges, which in certaincircumstances can be advantageous. It will also be appreciated thatwhere a pair of sonotrodes are to act on a single grid as described, itis not essential for the two sonotrodes to be side by side. Anotherarrangement is to feed the grids vertically and to supply paste, forexample in the form of strips, to each side of the grid, the paste beingacted upon by a pair of sonotrodes at opposite sides of the grid.

If necessary, the bar 24 could be rotated from time to time and cleaned.

In the example described above, a pair of sonotrodes must be used, butit has been found that a wider sonotrode than those commerciallyavailable can be used if the sonotrode is formed with n parallel, closedended slots which divide the sonotrode into n+1 portions ofsubstantially equal width, said slots extending generally parallel tothe direction of vibration of the sonotrode in use. 2 An example of sucha sonotrode is shown in FIGS. 6 and 7. The sonotrode is formed from asubstantially rectangular block 111 of metal, of substantiallytriangular cross-section. Extending into the block 111, from themid-point of the upper face thereof (as shown in the drawings) is ascrew-threaded bore 112, which in use receives a correspondinglyscrew-threaded shank, whereby the sonotrode is secured to the velocitytransformer of an ultrasonic tool. Between the upper and lower edges ofthe block 111, the block 111 is formed with a pair of parallel, closedended slots 113, which divide the block into three substantially equallydimensioned portions 114. The width of these portions 114 must not ofcourse exceed the maximum permitted width for a single sonotrode.

FIGS. 6 and 7, which are not drawn to scale, indicate various dimensionswhich in the preferred embodiment had the following values in inches:

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. Apparatus for manufacturing a battery plate for a lead-acid battery,the apparatus having the following features:

a. a support member b. means for heating the support member duringoperation of said apparatus c. a probe disposed opposite said supportmember and defining with said support member a gap therebetween d.conveyor means for transporting through and between said gap a batteryplate gridhaving thereon a lead-based paste with one surface of saidgrid in contact with said support member e. means for adjusting therelative positions of the support member and probe whereby said probedips into said paste while said grid rests on said sup port member f.means vibrating said probe at a frequency to change the consistency ofsaid paste while said grid is in contact with said support member,whereby said paste flows into said grid.

2. Apparatus for manufacturing a battery plate, comprising an ultrasonictool including a sonotrode, a support positioned beneath said sonotrodeand accurately positioned relative thereto, and feed means fortraversing a battery plate grid having a paste of material on one facethereof over and in contact with said support and past the sonotrodewhereby the sonotrode dips into the paste and causes the paste to flowinto the interstices of the portion of the grid in contact with thesupport, said sonotrode presenting an inclined surface to said grid,said surface defining means guiding the paste on the grid beneath thesonotrode.

3. Apparatus as claimed in claim 3 including means for heating thesupport.

4. Apparatus as claimed in claim 2 in which the angle between saidsurface and the grid is between 30 and 45.

5. Apparatus as claimed in claim 2 including means for inverting thegrid after it has passed the sonotrode, and further feed means fortransversing the inverted grid past a second sonotrode which smooths thepaste which is caused to flow through the grid by the firstmentionedsonotrode.

6. Apparatus as claimed in claim 5 including means for supplying afurther paste material to the grid after it is inverted but before itpasses the second sonotrode.

7. Apparatus for manufacturing a battery plate for a lead-acid battery,the apparatus having the following features:

a. a fixed support b. means for heating the support c. a probe definingwith said support a gap d. a paste containing hopper laterally spacedfrom the probe and support.

e. conveyor means for transporting a battery plate grid beneath saidhopper, whereupon paste is deposited on said grid f. said conveyor meansthen transporting the grid through said gap g. means for adjusting therelative positions of the support and probe whereby said probe clipsinto said paste while said grid rests on said support.

h. means vibrating said probe at a frequency to change the consistencyof said paste, whereby said paste flows into said grid.

8. Apparatus for manufacturing battery plates, the

apparatus having the following features:

a. a probe;

b. a support disposed opposite said probe and defining a gaptherebetween;

c. driven conveyor means for transporting through and between said gap abattery plate grid having thereon a paste which is to be introduced intothe grid, said paste having such consistency that it does not flow intothe grid, said conveyor means moving said grid past the probe with onesurface of said grid in contact with said support;

(1. said probe and said support being spaced apart and positioned sothat said probe dips into said paste while said grid rests on saidsupport;

e. means vibrating said probe at a frequency to change the consistencyof said paste while said grid is in contact with said support, wherebysaid paste flows into said grid.

9. Apparatus for manufacturing a battery plate, comprising an ultrasonictool including a sonotrode, a support positioned beneath said sonotrodeand accurately positioned relative thereto, and feed means fortraversing a battery plate grid having a paste of material on one facethereof over said support and past the sonotrode whereby the sonotrodedips into the paste and causes the paste to flow into the interstices ofthe portion of the grid on the support, said sonotrode presenting aninclined surface to said grid and guiding the paste on the grid beneaththe sonotrode, and the apparatus including guide plates associated withthe sonotrode for minimizing spillage of paste in a direction at rightangles to the travel of the grid.

10. Apparatus for manufacturing a battery plate,

comprising an ultrasonic tool including a sonotrode, a

support positioned beneath said sonotrode and accurately positionedrelative thereto, and feed means for traversing a battery plate gridhaving a paste of material on one face thereof over said support andpast the sonotrode whereby the sonotrode dips into the paste and causesthe paste to flow into the interstices of the portion of the grid on thesupport, said sonotrode presenting an inclined surface to said grid andguidingthe paste on the grid beneath the sonotrode, and said sonotrodebeing formed with N parallel closed ended slots which divide thesonotrode into N+l portions of substantially equal width, said slotsextending generally parallel to the direction of vibration of thesonotrode in use.

1. Apparatus for manufacturing a battery plate for a lead-acid battery,the apparatus having the following features: a. a support member b.means for heating the support member during operation of said apparatusc. a probe disposed opposite said support member and defining with saidsupport member a gap therebetween d. conveyor means for transportingthrough and between said gap a battery plate grid having thereon alead-based paste with one surface of said grid in contact with saidsupport member e. means for adjusting the relative positions of thesupport member and probe whereby said probe dips into said paste whilesaid grid rests on said support member f. means vibrating said probe ata frequency to change the consistency of said paste while said grid isin contact with said support member, whereby said paste flows into saidgrid.
 2. Apparatus for manufacturing a battery plate, comprising anultrasonic tool including a sonotrode, a support positioned beneath saidsonotrode and accurately positioned relative thereto, and feed means fortraversing a battery plate grid having a paste of material on one facethereof over and in contact with said support and past the sonotrodewhereby the sonotrode dips into the paste and causes the paste to flowinto the interstices of the portion of the grid in contact with thesupport, said sonotrode presenting an inclined surface to said grid,said surface defining means guiding the paste on the grid beneath thesonotrode.
 3. Apparatus as claimed in claim 3 including means forheating the support.
 4. Apparatus as claimed in claim 2 in which theangle between said surface and the grid is between 30* and 45*. 5.Apparatus as claimed in claim 2 including means for inverting the gridafter it has passed the sonotrode, and further feed means fortransversing the inverted grid past a second sonotrode which smooths thepaste which is caused to flow through the grid by the first-mentionedsonotrode.
 6. Apparatus as claimed in claim 5 including means forsupplying a further paste material to the grid after it is inverted butbefore it passes the second sonotrode.
 7. Apparatus for manufacturing abattery plate for a lead-acid battery, the apparatus having thefollowing features: a. a fixed support b. means for heating the supportc. a probe defining with said support a gap d. a paste containing hopperlaterally spaced from the probe and support. e. conveyor means fortransporting a battery plate grid beneath said hopper, whereupon pasteis deposited on said grid f. said conveyor means then transporting thegrid through said gap g. means for adjusting the relative positions ofthe support and probe whereby said probe dips into said paste while saidgrid rests on said support. h. means vibrating said probe at a frequencyto change the consistency of said paste, whereby said paste flows intosaid grid.
 8. Apparatus for manufacturing battery plates, the apparatushaving the following features: a. a probe; b. a support disposedopposite said probe and defining a gap therebetween; c. driven conveyormeans for transporting through and between said gap a battery plate gridhaving thereon a paste which is to be introduced into the grid, saidpaste having such consistency that it does not flow into the grid, saidconveyor means moving said grid past the probe with oNe surface of saidgrid in contact with said support; d. said probe and said support beingspaced apart and positioned so that said probe dips into said pastewhile said grid rests on said support; e. means vibrating said probe ata frequency to change the consistency of said paste while said grid isin contact with said support, whereby said paste flows into said grid.9. Apparatus for manufacturing a battery plate, comprising an ultrasonictool including a sonotrode, a support positioned beneath said sonotrodeand accurately positioned relative thereto, and feed means fortraversing a battery plate grid having a paste of material on one facethereof over said support and past the sonotrode whereby the sonotrodedips into the paste and causes the paste to flow into the interstices ofthe portion of the grid on the support, said sonotrode presenting aninclined surface to said grid and guiding the paste on the grid beneaththe sonotrode, and the apparatus including guide plates associated withthe sonotrode for minimizing spillage of paste in a direction at rightangles to the travel of the grid.
 10. Apparatus for manufacturing abattery plate, comprising an ultrasonic tool including a sonotrode, asupport positioned beneath said sonotrode and accurately positionedrelative thereto, and feed means for traversing a battery plate gridhaving a paste of material on one face thereof over said support andpast the sonotrode whereby the sonotrode dips into the paste and causesthe paste to flow into the interstices of the portion of the grid on thesupport, said sonotrode presenting an inclined surface to said grid andguiding the paste on the grid beneath the sonotrode, and said sonotrodebeing formed with N parallel closed ended slots which divide thesonotrode into N+1 portions of substantially equal width, said slotsextending generally parallel to the direction of vibration of thesonotrode in use.